It is understood that conventional amplifier designs have several opportunities for improvement. This becomes readily apparent when the amplifiers are deployed in applications where size, weight and power are limited factors. First, direct current electronic components occupy a significant percentage of the total amplifier volume, and in many amplifier applications, space and weight come at a premium. Multiple internal voltages are required (e.g., +24V, +5V, +3.3V, −4V, −5V) and in some applications the use of on-board regulators are incorporated for each of the required voltages to reduce the potential susceptibility to electromagnetic fields which may be present in the external environment. Confining the amplifier power interface to a single input voltage, which is immediately followed by internal regulators, allows filtering of noise which might otherwise be injected by those external fields. In addition to maintaining regulation of the various voltage levels it is important in some cases that the turn on and turn off of the individual voltages be properly sequenced to avoid catastrophic damage. Another factor of the size, weight and power constraints in some applications is thermal management. An amplifier that operates at full power may generate heat that can raise the internal operating temperatures which affects the performance of the amplifier as well as other components. This can lead to lower performance and less than optimal operation.
Conventional systems require multiple input connector pins and have a costly die and wire bond construction, with multiple adjustment points (e.g., delay times, offsets, scale factor) in order to provide for applying different voltages prior to and after a prescribed burn-in period associated with the semiconductor die used in the amplifier. Currently, these systems require invasive, labor intensive trim processes utilizing wire bonds and thin film resistor networks to provide for needed optimization of gate bias operating points and performance across the operating temperature range. Further, the high component count present in conventional systems requires significant board area and the currently available single slope temperature compensation are less than ideal.
Wherefore it is an object of the present disclosure to overcome the above-mentioned shortcomings and drawbacks associated with the conventional radio frequency amplifiers.